What universally accepted biological characteristic helps confirm an insect is a bee due to pollen collection efficiency?

Answer

Possessing branched hairs across their bodies.

Bees possess branched hairs across their bodies, which are much more complex than the simple, straight hairs found on many wasps, enabling them to trap pollen grains effectively.

What universally accepted biological characteristic helps confirm an insect is a bee due to pollen collection efficiency?
animalinsectbeeclassification